Objectives: This study aimed to analyze the efficacy of single-dose tranexamic acid (TA) 20 mg/kg preoperatively to reduce blood loss in patients undergoing total knee replacement (TKR).Methods: A total of 387 patients (82 males, 305 females) undergoing TKR between January 2014 and December 2018 were included in the study. The T + group was administrated intravenous (iv) TA 20 mg/kg 20 min before the skin incision. We determined perioperative blood loss, the amount of drainage postoperative 24 h, the amount of drainage after postoperative 2448 h, total volume of drains, total volume of blood loss, postoperative hemoglobin and hematocrit levels, and amount of total blood transfusion.Results: In terms of demographic data, no statistically significant difference was observed between the groups. Perioperative blood loss and total volume of blood loss was found statistically higher in T − group compared to T + group. Postoperatively, the mean hemoglobin and hematocrit levels of T − group were statistically significantly lower than T + group.Conclusion: A single 20 mg/kg iv TA administration before TKR reduces bleeding during surgery and within 24 h postoperatively.